1. Field
The technology relates to a display device and a driving method thereof. More particularly, the technology relates to a display device and a driving method thereof which has better quality on the edges of the display device at a high temperature.
2. Description of the Related Technology
As a representative flat panel display device, a liquid crystal display (LCD) includes two display panels with pixel electrodes and a common electrode, and a liquid crystal layer having an anisotropic dielectric interposed between the two panels. The pixel electrodes are arranged in a matrix and are connected to switches such as thin film transistors (TFT) to sequentially receive a data voltage by row. The common electrode is formed over the entire surface of the display panel to receive a common voltage. The pixel electrodes, the common electrode, and the liquid crystal layer interposed between the pixel electrodes and the common electrode form a liquid crystal capacitor, and the liquid crystal capacitor and a switch connected thereto are a basic unit forming a pixel.
In an LCD, an electric field is generated in the liquid crystal layer by applying voltages to the two electrodes, and transmittance of light passing through the liquid crystal layer of each of the pixels is controlled by controlling the electric fields to display a desired image. In order to prevent degradation of the display caused by a lengthy application of an electric field in one direction to a liquid crystal layer, polarity of the data voltage with respect to the common voltage is inverted for respective frames, respective rows, or respective pixels.
A common electrode panel including the common electrode and a thin film transistor array panel including the pixel electrode are fixed by a sealant formed on the edge thereof. Ionic particles may be generated by the sealant because of heat generated during the sealing operation, during the lifetime of the display device, or heat generated in the external environment. The ionic particles are generally around the outer edge of the display and have a certain charge polarity because of the voltage applied to the common electrode and the pixel electrode. Because of the charge, the particles are fixed to the common electrode and the pixel electrode on the edge of the display device such that a residual DC voltage is generated. The threshold of the liquid crystal is altered by the residual DC voltage and visual artifacts may thereby be formed on the edge of the display device.
The above information disclosed in this Background section is only for enhancement of understanding of the background and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.